We hope to gain a greater understanding of the role of membrane lipids in the synthesis, integration and function of membrane proteins. In this grant period we will extend our work on the energy transducing Ca ions, Mg ions ATPase of E. coli to include studies on biogenesis. In addition, we will examine the biogenesis of the transport protein(s) for Beta-glucosides, the Enzyme IIbgl of the PEP-sugar phosphotransferase system (PTS). A major objective of these studies is to determine the role of lipids in directing a polypeptide to a membrane destination. We plan to complete model system studies to determine the physical properties of asymmetric phospholipid bilayers and the development of "side specific" fluorescent probes. We will also extend and complete studies of reconstituted lipid/protein vesicles using the coat protein from a filamentous E. coli phage M13 (Ml3CP) and the peptide melittin. The major objective of this work is to develop the expertise for examining lipid/protein interactions in real membranes. We will continue our studies on metabolism of membrane lipids in cultured animal cells. We will extend nutritional mutational methods for altering the lipid composition of cells. Our major interest will be to determine the physical and functional consequences of lipid alterations. The objective of this work is to develop an understanding of those cellular functions that may depend on lateral diffusion of membrane surface components.